My favorite was dark/dark/leviathan (whirlpool with -res). Will never be popular, will never be OP, but was a lot of fun, worked at all content, including master of runs and the hardest incarnate badging attempts.
/dark is like an onion, you get lots of layers. def, res, heal, -tohit, fears... you get it all. Nothing is overwhelming or inately maxxed out, but it was very reliable against every enemy type. Sappers, furies, ppd, cimerorans, rikti magus/heavies, carnies, incarnates, etc.
I imagine no one will ever play it these days because it can't farm +4/x8 solo. But speaking as one who enjoys actual missions and story arcs in teams, this was the most fun I ever had with a stalker.